U.S. Pat. No. 2,368,687 (Stanley 1945) is an example of a folding coin purse. The Stanley coin purse consists of an inner flat layer and an outer flat layer of material peripherally stitched to each other. An open access window is provided in one half of the inner flat layer, leaving a loose narrow peripheral margin. The open access window allows the user to view coins within the coin purse and it has a tab to pull up with another hand to lift the end wall up when shuffling coins. The peripheral margin confines the coins. The coin purse folds in half, over the access window, to assume a closed position.
Japanese Patent application 2000357237 (Kojima 2000) similarly discloses a folding coin purse with an inner layer and an outer layer. The inner layer has two “U” shaped peripheral margins arranged in end to end relation, with a transparent material closing in the “U” shape of one half to form a transparent pocket. There is a gap between the “U” shaped peripheral margins, which facilitates the coin purse folding in half. The Kojima patent mentions fixed walls, which means that they are not collapsible.